沼氣提純精制天然氣中脫硫技術路線的選擇應重點考慮硫化氫濃度、處理規模、濃度波動范圍、處理費用等幾個方面。當硫化氫濃度較高及處理規模較大時,易采用堿洗生物再生脫硫技術和或堿洗催化再生脫硫技術。在運行成本面前相對后者較低,但在抗濃度變化沖擊方面,后者又優于前者,同時在投資方面,后者也優于前者。
The selection of desulfurization technology route in biogas purification and refining natural gas should focus on hydrogen sulfide concentration, treatment scale, concentration fluctuation range and treatment cost. When the concentration of hydrogen sulfide is high and the treatment scale is large, alkali washing biological regeneration desulfurization technology and alkali washing catalytic regeneration desulfurization technology are easy to be used. Compared with the latter, the latter is lower in terms of operation cost, but in terms of resisting the impact of concentration change, the latter is better than the former, and in terms of investment, the latter is also better than the former.
生物脫硫工藝是一種新型的脫硫工藝,越來越受到企業的歡迎。生物脫硫的基本原理是利用硫桿菌屬和絲硫茵屬類微生物代謝的作用,將硫化氫與氧氣合成為硫酸鹽進而除去沼氣中的硫氫,脫硫產物為硫酸鹽。
Biological desulfurization process is a new type of desulfurization process, which is more and more welcomed by enterprises. The basic principle of biological desulfurization is to synthesize hydrogen sulfide and oxygen into sulfate and then remove hydrogen sulfide from biogas by utilizing the metabolism of microorganisms of Thiobacillus and sericin, and the desulfurization product is sulfate.
雖然其使用較為便捷,運行成本較低,但由于脫硫過程中同時引入了雜質氣體,在后續工序中無法去除,同時生物脫硫剛剛起步,技術還不成熟,大多使用進口技術和設備,因此投資成本相對較高,大約為常規干法脫硫的3~5倍。
Although its use is relatively convenient and its operation cost is low, because impurity gas is introduced in the desulfurization process at the same time, it can not be removed in the subsequent process. At the same time, biological desulfurization has just started and the technology is not mature. Most of them use imported technology and equipment, so the investment cost is relatively high, about 3-5 times as that of conventional dry desulfurization.
近幾年,國內少數企業和科研機構合作研究,根據沼氣項目及沼氣中硫化氫的特性,對堿洗催化再生脫硫技術進行了大量富有成效的改進和提升,特別是解決了像堵塔、再生效果不好、單質硫不易拿出等高濃度硫化氫脫除上的難題。
In recent years, a small number of domestic enterprises and scientific research institutions have cooperated to study, according to the characteristics of biogas projects and hydrogen sulfide in biogas, a large number of fruitful improvements and improvements have been made to the alkali washing catalytic regeneration desulfurization technology, especially to solve the problems of high concentration hydrogen sulfide removal such as blocking tower, poor regeneration effect and difficulty in extracting elemental sulfur.
干法脫硫、PSA和膜法脫硫多適用于硫化氫初脫后的精脫硫,或氣量比較小、硫化氫濃度比較低的沼氣精制項目; 生物脫硫雖然運行成本比較低,但因為引入了大量的氮氧等雜質氣體而不宜在沼氣精制天然氣領域應用。
Dry desulfurization, PSA and membrane desulfurization are mostly suitable for refined desulfurization after initial desulfurization of hydrogen sulfide, or for biogas refining projects with small gas volume and low concentration of hydrogen sulfide. Although biological desulfurization has low operation cost, it is not suitable to be applied in the field of biogas refining natural gas because of the introduction of a large number of impurity gases such as nitrogen and oxygen.